WASHINGTON (CNN) -- At a campaign stop in Houston Friday, former New York City Mayor Rudy Giuliani fully explained his views on abortion, saying that he is morally against the procedure but firmly believes that a woman should have the right to choose to end her pregnancy.

"I believe you have to respect their viewpoint and give them a level of choice here," the Republican presidential candidate said at Houston Baptist University. "Because I think ultimately, even if you disagree, you have to respect the fact that their conscience is as strong as yours is about this and they're the ones that are most affected by it."

Giuliani said he is understands that his abortion views will turn some Republican "single issue" voters away. But he encouraged them to look at the big picture and pick their candidate based on issues like fighting terrorism.

"We have got to unite in this election," Giuliani said. "Because if we don't unite and we don't find a way of uniting around broad principles that will appeal to a large section of this country, if we can't figure that out, then we're going to lose this election."

--CNN Associate Producer Lauren Kornreich